You will soon come to the second tile set. These will complete the bridge on the second level.

Pass through this narrow gap between the pool and the wall.

You'll find a broken circuit.

Light it up with Yellow Pikmin.

This will cause flowers to bloom near the bridge, creating a new path. A narrow ledge just ahead of you next to the tunnel you entered from leads up. If you have time, proceed to the second floor and follow the instructions listed in our Exploration Day 24 guide.